Techniques for guided advancement of a tool

ABSTRACT

A sheath is transluminally introduced a sheath into an atrium of a heart of a subject. A guide member is advanced out of the sheath and to a chorda tendinea of the heart, the guide member having a proximal portion that includes a longitudinal element, and a distal portion that includes a helical chord-engaging element. The chord-engaging element is wrapped around the chorda tendinea. While the chord-engaging element remains wrapped around the chorda tendinea, (i) the chord-engaging element is slid over the chorda tendinea toward a papillary muscle that is coupled to the chorda tendinea; and (ii) subsequently, a tool is moved out of the sheath and toward the papillary muscle by sliding the tool along the longitudinal element. Other embodiments are also described.

CROSS-REFERENCES TO RELATED APPLICATIONS

The present application is a Continuation of U.S. Ser. No. 15/669,003 toReich et al., filed Aug. 4, 2017, and entitled “Techniques forguide-wire based advancement of a tool,” which published as US2017/0325958, and which is a Divisional of U.S. Ser. No. 14/650,114 toReich et al., filed Jun. 5, 2015, and entitled “Techniques forguide-wire based advancement of a tool,” which published as US2015/0297212 (now U.S. Pat. No. 9,730,793), and which is the US NationalPhase of PCT application IL2013/050992 to Reich et al., filed Dec. 3,2013, and entitled “Techniques for guide-wire based advancement of atool,” which published as WO 2014/087402, and which claims priority fromU.S. Provisional Patent application 61/733,979 to Reich et al., filedDec. 6, 2012, and entitled “Techniques for guide-wire based advancementof a tool.”

The present application is related to:

(a) International Application PCT/IL2011/000446 to Miller et al.,entitled “Apparatus and method for guide-wire based advancement of arotation assembly,” filed on Jun. 6, 2011 (which published asWO/2011/154942);

(b) U.S. patent application Ser. No. 12/795,192 to Miller et al.,entitled “A method for guide-wire based advancement of a rotationassembly,” filed on Jun. 7, 2010 (which published as US 2011/0301698)(now U.S. Pat. No. 8,690,939);

(c) U.S. patent application Ser. No. 12/795,026 to Miller et al.,entitled “Apparatus for guide-wire based advancement of a rotationassembly,” filed on Jun. 7, 2010 (which published as US 2011/0106245)(now U.S. Pat. No. 8,940,042), which is a continuation-in-part of U.S.patent application Ser. No. 12/608,316 to Miller et al., entitled,“Tissue anchor for annuloplasty device,” filed on Oct. 29, 2009 (nowU.S. Pat. No. 8,277,502); and

(d) U.S. patent application Ser. No. 13/707,013 to Reich et al.,entitled “Apparatus and method for guide-wire based advancement of arotation assembly”, filed on Dec. 6, 2012 (which published as US2013/0096672) (now U.S. Pat. No. 9,180,007).

All of these applications are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates in general to valve and chordae tendineaerepair. More specifically, the present invention relates to repair of anatrioventricular valve and associated chordae tendineae of a patient.

BACKGROUND

Ischemic heart disease causes mitral regurgitation by the combination ofischemic dysfunction of the papillary muscles, and the dilatation of theleft ventricle that is present in ischemic heart disease, with thesubsequent displacement of the papillary muscles and the dilatation ofthe mitral valve annulus.

Dilation of the annulus of the mitral valve prevents the valve leafletsfrom fully coapting when the valve is closed. Mitral regurgitation ofblood from the left ventricle into the left atrium results in increasedtotal stroke volume and decreased cardiac output, and ultimate weakeningof the left ventricle secondary to a volume overload and a pressureoverload of the left atrium.

Chronic or acute left ventricular dilatation can lead to papillarymuscle displacement with increased leaflet tethering due to tension onchordae tendineae, as well as annular dilatation.

SUMMARY OF THE INVENTION

In some applications of the present invention, apparatus is providedcomprising an implant comprising one or more primary adjustable repairchords and an adjustment mechanism that is configured to adjust atension of the one or more adjustable repair chords and that is slidablealong a guidewire toward an implantation site. Additionally, theapparatus comprises a first tissue-engaging element (e.g., a tissueanchor) that comprises one or more docking stations. Furtheradditionally, in accordance with some applications of the presentinvention, a method is provided for implanting such apparatus. Arespective guidewire is reversibly coupled to each one of the dockingstations. The adjustment mechanism is slidable along the guidewiretoward one of the one or more docking stations, and is coupled to thetissue-engaging element via the docking station. Thus, the dockingstation is a coupling element that provides coupling between two otherelements (in this case, between adjustment mechanism and thetissue-engaging element.)

The repair chord comprises a flexible, longitudinal member (e.g.,sutures or wires). The repair chord is coupled at a distal portionthereof to the adjustment mechanism. In some applications, the repairchord functions as artificial chordae tendineae. In other applications,the repair chord is used to adjust a distance between two portions ofthe ventricular wall. For some applications, the repair chord is coupledat a proximal portion thereof to a second tissue-engaging element (e.g.,a tissue anchor which penetrates or clips a portion of tissue).

For other applications, the repair chord comprises a cord that isdisposed within at least a portion of an annuloplasty ring structure(e.g., a full annuloplasty ring or a partial annuloplasty ring). Forsuch applications, the annuloplasty ring structure comprises theadjustment mechanism that is coupled to the repair cord. Theannuloplasty ring structure is slidable along the guidewire toward oneof the one or more docking stations, and is coupled to thetissue-engaging element via the docking station. It is to be noted thatthe annuloplasty ring structure may be provided independently of theadjustment mechanism and the repair chord. For such applications, theannuloplasty ring structure is slidable along the guidewire toward oneof the one or more docking stations, and is coupled to thetissue-engaging element via the docking station.

For yet other applications, a prosthetic heart valve and/or a supportfor the prosthetic heart valve is slidable along the guidewire towardone of the one or more docking stations, and is coupled to thetissue-engaging element via the docking station.

Thus, the tissue-engaging element and the docking station are used tofacilitate implantation of an implant such as cardiac valve implants,namely annuloplasty ring structures, prosthetic valves, and/or apparatusfor receiving a prosthetic valve (e.g., a docking station or a supportfor receiving the prosthetic valve).

Typically, during a transcatheter procedure, the first tissue-engagingelement is coupled to a first portion of tissue at a first implantationsite in a heart of a patient. The adjustment mechanism is then slidalong the guidewire and toward the first tissue-engaging element at thefirst implantation site. The proximal portion of the repair chord isthen coupled via the second tissue-engaging element to a second portionof tissue at a second implantation site. Following the coupling of thesecond tissue-engaging element to the second implantation site, theadjustment mechanism is further slid distally toward the firsttissue-engaging element and is then coupled to the first tissue-engagingelement via the one or more docking stations on the firsttissue-engaging element. Following the coupling of the adjustmentmechanism to the second tissue-engaging element, a length and tension ofthe repair chord is then adjusted in order to adjust a distance betweenthe first and second implantation sites. For applications in which therepair chord functions as an artificial chordae tendineae, theadjustment of the length and tension of the repair chord draws theleaflets together, and/or pulls the leaflet down toward the firstimplantation site to repair the valve.

In some applications of the present invention, the adjustment mechanismcomprises a spool assembly which adjusts a degree of tension of therepair chord. The spool assembly comprises a housing, which houses aspool to which a distal portion of the repair chord is coupled.

For applications in which the repair chord is coupled to two respectiveportions of the ventricular wall, the two portions are drawn together,thereby restoring the dimensions of the heart wall to physiologicaldimensions, and drawing the leaflets toward one another.

In some applications of the present invention, the adjustment mechanismcomprises a reversible locking mechanism which facilitates bidirectionalrotation of the spool in order to effect both tensioning and relaxing ofthe repair chord. That is, the spool is wound in one direction in orderto tighten the repair chord, and in an opposite direction in order toslacken the repair chord. Thus, the spool adjustment mechanismfacilitates bidirectional adjustment of the repair chord.

In some applications of the present invention, the adjustable repairchord is implanted during an open-heart or minimally-invasive procedure.In these applications, the delivery tool comprises a handle and amultilumen shaft that is coupled at a distal end thereof to theadjustment mechanism. The delivery tool functions to advance theadjustment mechanism to the first portion of tissue, implant theadjustment mechanism at the first portion of tissue, and effectadjustment of the repair chord by effecting rotation of the spool. Forapplications in which the repair chord functions as an artificialchordae tendineae, prior to implantation of the adjustment mechanism,the distal portion of the delivery tool and the adjustment mechanismcoupled thereto are advanced between the leaflets of theatrioventricular valve and into the ventricle toward the first portionof tissue. The incision made in the heart is then closed around thedelivery tool and the heart resumes its normal function during theadjustment of the length of the artificial chordae tendineae.

In some applications of the present invention, apparatus and methoddescribed herein may be used for providing artificial chordae tendineaein a left ventricle of the heart and effecting adjustment thereof. Insome applications, apparatus and method described herein may be used forproviding artificial chordae tendineae in a right ventricle of the heartand effecting adjustment thereof. In some applications, apparatus andmethod described herein may be used for providing a system to adjust alength between two portions of the heart wall. For other applicationsapparatus and method described herein may be used for providing adocking station for an annuloplasty ring or for a prosthetic valve.

In some applications of the present invention, a guide member,comprising a chord-engaging element that is slidably couplable tochordae tendineae of the patient is used to guide a deployment tool to apapillary muscle of the patient, so as to facilitate anchoring of atissue anchor (e.g., a tissue anchor of a docking assembly) to thepapillary muscle.

There is therefore provided, in accordance with an application of thepresent invention, apparatus for facilitating anchoring of a tissueanchor to a papillary muscle of a heart of a subject, the papillarymuscle being coupled to one or more chordae tendineae of the heart ofthe subject, the apparatus being configured to be used with a guidewire,and including:

a housing, percutaneously deliverable to the heart of the subject,slidable along the guidewire, and shaped to define at least one opening;

a guide member, percutaneously deliverable to the heart of the subject,percutaneously removable from the subject, couplable to the housing, andhaving:

-   -   a distal portion, including a chord-engaging element, configured        to be percutaneously slidably coupled to at least one of the one        or more chordae tendineae, and decouplable from the at least one        of the one or more chordae, and    -   a proximal portion, including a longitudinal element; and

a deployment tool, configured (1) to be reversibly coupled to theanchor, (2) to be slidably coupled to the longitudinal element of theguide member, and (3) to anchor the tissue anchor to the papillarymuscle of the subject.

In an application, the housing is configured to be decoupled from theguide member before the deployment tool is coupled to the guide member.

In an application, the tissue anchor includes a helical tissue anchor,and the deployment tool is configured to anchor the tissue anchor to thepapillary muscle of the subject by rotating the tissue anchor.

In an application, the deployment tool includes a lance, configured tostabilize the deployment tool at the papillary muscle of the subject bypenetrating tissue of the papillary muscle.

In an application, the lance is retractable into the deployment tool.

In an application, the apparatus further includes the anchor.

In an application, the guidewire includes a first guidewire, and theapparatus further includes a second guidewire, reversibly coupled to theanchor.

In an application, the apparatus further includes the guidewire, theguidewire being configured to be transluminally advanced to a vicinityof the one or more chordae tendineae of the subject.

In an application, the guidewire is configured to be transluminallyadvanced such that a distal portion of the guidewire is disposed betweenat least two chordae tendineae of the subject, the one or more chordaetendineae including at least one of the at least two chordae tendineaeof the subject.

In an application, the housing is shaped to define a channeltherethrough, the housing being slidable along the guidewire by theguidewire being slidable through the channel.

In an application, the chord-engaging element includes a helicalelement, configured to be housed by the housing, to be advanced out ofthe housing, and to form a helix outside of the housing.

In an application, the chord-engaging element is configured to begenerally straight when housed by the housing, and to curl into thehelix outside of the housing.

In an application, the chord-engaging element is configured to behelical when housed by the housing.

There is further provided, in accordance with an application of thepresent invention, a method for use with a papillary muscle of a heartof a subject, the papillary muscle being coupled to one or more chordaetendineae of the heart of the subject, the method including:

advancing a guide member to the chordae tendineae, the guide memberhaving a proximal portion that includes a longitudinal element, and adistal portion that includes a chord-engaging element, configured to beslidably coupled to the chordae tendineae;

coupling the chord-engaging element to at least one of the one or morechordae tendineae;

sliding the chord-engaging element over the at least one of the chordaetendineae toward the papillary muscle; and

advancing a tool toward the papillary muscle of the subject by slidingthe tool along the longitudinal element.

In an application, the chord-engaging element includes a helicalchord-engaging element, and coupling the chord-engaging element to theat least one of the chordae tendineae includes wrapping the helicalchord-engaging element around the at least one of the chordae tendineae.

In an application, the method further includes, following the step ofadvancing, anchoring a tissue anchor to ventricular muscle tissue usingthe tool.

In an application, anchoring the tissue anchor includes anchoring thetissue anchor to ventricular muscle tissue in a vicinity of thepapillary muscle.

In an application, anchoring the tissue anchor includes anchoring thetissue anchor to ventricular muscle tissue within 1 cm of the papillarymuscle.

In an application, anchoring the tissue anchor includes anchoring thetissue anchor to the papillary muscle.

In an application, anchoring the tissue anchor includes anchoring atissue anchor that is reversibly couplable to a guidewire.

In an application, the deployment tool includes a lance, and the methodfurther includes, prior to anchoring the tissue anchor, stabilizing thetool with respect to the ventricular muscle tissue by penetrating theventricular muscle tissue with the lance.

In an application, the method further includes retracting the lance intothe deployment tool.

In an application, the step of advancing includes advancing, to theheart of the subject, a housing that is slidable along the guide member.

In an application, the method further includes, prior to the step ofadvancing, advancing a guidewire to a ventricle of the heart, andadvancing the housing includes sliding the housing over the guidewire.

In an application, advancing the guidewire includes advancing a distalportion of the guidewire between at least two of the chordae tendineaeof the subject.

In an application, the method further includes, subsequent to the stepof advancing, sliding the chord-engaging element distally out of thehousing.

In an application, the method further includes, subsequent to the stepof coupling and prior to the step of advancing, proximally withdrawingthe housing and decoupling the housing from the guide member whilemaintaining the coupling of the chord-engaging element to the at leastone of the one or more chordae tendineae.

In an application, sliding the chord-engaging element distally out ofthe housing includes facilitating transitioning of the chord-engagingelement from a generally straight state into a helical state.

There is further provided, in accordance with an application of thepresent invention, a method for use with a tissue anchor and a papillarymuscle of a heart of a subject, the papillary muscle being coupled toone or more chordae tendineae of the heart of the subject, the methodincluding:

percutaneously advancing to the chordae tendineae, along a guidewirethat has been advanced to the chordae tendineae of the subject, ahousing, shaped to define at least one opening;

advancing a distal portion of a guide member out of the opening of thehousing, the distal portion of the guide member including achord-engaging element;

coupling the chord-engaging element to at least one of the one or morechordae tendineae;

exposing a proximal portion of the guide member out of the opening ofthe housing by withdrawing the housing proximally with respect to theguide member, the proximal portion of the guide member including alongitudinal element; and

anchoring the tissue anchor to ventricular muscle tissue of the subjectby advancing a deployment tool, reversibly couplable to the tissueanchor, along the longitudinal element.

In an application, the method further includes, subsequently to the stepof coupling and prior to the step of anchoring, sliding thechord-engaging element along the at least one chordae tendineae towardthe papillary muscle.

In an application, the method further includes decoupling the housingfrom the guide member before advancing the deployment tool along thelongitudinal member.

In an application, the tissue anchor includes a helical tissue anchor,and anchoring the tissue anchor includes rotating the tissue anchor.

In an application, the guidewire includes a first guidewire, andanchoring the tissue anchor includes anchoring a tissue anchor that isreversibly couplable to a second guidewire.

In an application, anchoring the tissue anchor includes anchoring thetissue anchor to ventricular muscle tissue in a vicinity of thepapillary muscle.

In an application, anchoring the tissue anchor includes anchoring thetissue anchor to ventricular muscle tissue within 1 cm of the papillarymuscle.

In an application, anchoring the tissue anchor includes anchoring thetissue anchor to the papillary muscle.

In an application, the deployment tool includes a lance, and the methodfurther includes, before anchoring the tissue anchor, stabilizing thedeployment tool with respect to the ventricular muscle tissue bypenetrating the ventricular muscle tissue with the lance.

In an application, the method further includes retracting the lance intothe deployment tool.

In an application, the step of advancing includes advancing thechord-engaging element out of the opening of the housing such that thechord-engaging element forms a helix outside of the housing.

In an application, advancing the chord-engaging element out of theopening of the housing includes facilitating a transition of thechord-engaging member from a generally straight state into a helicalstate.

The present invention will be more fully understood from the followingdetailed description of applications thereof, taken together with thedrawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1-2 are schematic illustrations of apparatus comprising atissue-engaging element comprising a docking station coupled to aguidewire, in accordance with some applications of the presentinvention;

FIG. 3 is a schematic illustration of advancement of an adjustmentmechanism along the guidewire toward the docking station of FIGS. 1 and2, in accordance with some applications of the present invention;

FIGS. 4-5 are schematic illustrations of engaging a leaflet with aleaflet engaging element, in accordance with some applications of thepresent invention;

FIG. 6 is a schematic illustration of coupling of the adjustmentmechanism of FIG. 3 to the docking station, in accordance with someapplications of the present invention;

FIGS. 7-9 are schematic illustrations of adjusting by the adjustmentmechanism a length of a repair chord coupled to the adjustmentmechanism, in accordance with some applications of the presentinvention;

FIG. 10 is a schematic illustration of the adjustment mechanism and therepair chord, in accordance with some other applications of the presentinvention; and

FIGS. 11A-F are schematic illustrations of a system and techniques foruse thereof, for delivering a tissue anchor to a papillary muscle of asubject, in accordance with some applications of the invention.

DETAILED DESCRIPTION OF EMBODIMENTS

Reference is now made to FIGS. 1-2, which are schematic illustrations ofa system 20 comprising a docking assembly 150 for implantation at afirst implantation site 5 of a patient, in accordance with someapplications of the present invention. As shown in FIG. 2, dockingassembly 150 comprises a tissue-engaging element having (1) a distalportion comprising a tissue anchor 50 (e.g., a helical tissue anchor asshown by way of illustration and not limitation), and (2) a proximalportion comprising a docking platform 54, and at least one dockingstation 56. Thus, docking assembly 150 comprises (a) the distal portionwhich engages the tissue of the patient (i.e., the tissue-engagingelement), and (b) the proximal portion which is coupled to dockingstation 56. At least one guide member, (e.g., a guidewire 40, shown inFIG. 2) is reversibly coupled to docking assembly 150 (e.g., by beinglooped around, or otherwise coupled to, a portion of assembly 150) so asto define first and second portions 40 a and 40 a′ that extend away fromassembly 150.

Tissue anchor 50 is typically implanted within cardiac tissue in amanner in which a distal portion of anchor 50 does not extend beyond anepicardium of heart 2 of the patient. Thus, anchor 50 is implanted at anintracardiac site such that the implant, (e.g., the adjustment mechanismor an implant comprising the adjustment mechanism) that is eventuallycoupled thereto (as described hereinbelow) is implanted at theintracardiac site such that no portions of the adjustment mechanismextend beyond the epicardium of the heart.

Docking assembly 150 and guidewire 40 are advanced toward implantationsite typically during a transcatheter procedure, as shown. However, itis to be noted that the scope of the present invention includes theadvancement of assembly 150 and guidewire 40 during a minimally-invasiveor open-heart procedure. The procedure is typically performed with theaid of imaging, such as fluoroscopy, transesophageal echo, and/orechocardiography.

The transcatheter procedure typically begins with the advancing of asemi-rigid guidewire into a right atrium of the patient. The semi-rigidguidewire provides a guide for the subsequent advancement of a sheath 28therealong and into the right atrium. For some applications, once sheath28 has entered the right atrium, the semi-rigid guidewire is retractedfrom the patient's body. Sheath 28 typically comprises a 13-20 F sheath,although the size may be selected as appropriate for a given patient.Sheath 28 is advanced through vasculature into the right atrium using asuitable point of origin typically determined for a given patient. Forexample:

-   -   sheath 28 may be introduced into the femoral vein of the        patient, through an inferior vena cava, into the right atrium,        and into the left atrium transseptally, typically through the        fossa ovalis;    -   sheath 28 may be introduced into the basilic vein, through the        subclavian vein to the superior vena cava, into the right        atrium, and into the left atrium transseptally, typically        through the fossa ovalis; or    -   sheath 28 may be introduced into the external jugular vein,        through the subclavian vein to the superior vena cava, into the        right atrium, and into the left atrium transseptally, typically        through the fossa ovalis.

In some applications of the present invention, sheath 28 is advancedthrough the inferior vena cava of the patient (as shown) and into theright atrium using a suitable point of origin typically determined for agiven patient.

Sheath 28 is advanced distally until the sheath reaches the interatrialseptum. For some applications, a resilient needle and a dilator (notshown) are advanced through sheath 28 and into the heart. In order toadvance sheath 28 trans septally into the left atrium, the dilator isadvanced to the septum, and the needle is pushed from within the dilatorand is allowed to puncture the septum to create an opening thatfacilitates passage of the dilator and subsequently sheath 28therethrough and into the left atrium. The dilator is passed through thehole in the septum created by the needle. Typically, the dilator isshaped to define a hollow shaft for passage along the needle, and thehollow shaft is shaped to define a tapered distal end. This tapereddistal end is first advanced through the hole created by the needle. Thehole is enlarged when the gradually increasing diameter of the distalend of the dilator is pushed through the hole in the septum.

The advancement of sheath 28 through the septum and into the left atriumis followed by the extraction of the dilator and the needle from withinsheath 28. Subsequently, a docking-assembly delivery tool 30 is advancedthrough sheath 28. Tool 30 is typically advanced within a lumen of anadvancement sheath 22 having a distal end 24. Advancement sheath 22 isadvanced within sheath 28. Delivery tool 30 is coupled at a distal endthereof to a manipulator 32 which is reversibly coupled to dockingstation 56 and docking platform 54 of docking assembly 150. Manipulator32 has (1) lateral arms which cup platform 54, and (2) adocking-station-coupler 34, as shown in FIG. 1. Coupler 34 is biased tomove radially-inward, as shown in FIG. 1. Docking station 56 is ribbed,such that coupler 34, when moved radially inward, engages at least onerib of docking station 56, thereby coupling assembly 150 to deliverytool 30.

Delivery tool 30 and manipulator 32 are shaped so as to define a lumenfor passage therethrough of guidewire 40.

Docking assembly 150 is implanted in implantation site 5 by rotatingtool 30 in order to rotate anchor 50 and corkscrew anchor 50 into tissueof site 5. Site 5 typically comprises a portion of tissue at anintraventricular site in heart 2 of the patient. As shown, site 5includes a papillary muscle 4, by way of illustration and notlimitation. It is to be noted that site 5 includes any portion ofcardiac tissue, e.g., a portion of a free wall of the ventricle, aportion of the septum facing the ventricle, a portion of tissue at abase of the papillary muscle, or a portion of the wall at the apex ofthe ventricle. (For the purposes of the claims, “a portion of tissue ofa ventricle” includes any portion of cardiac tissue, e.g., a portion ofa free wall of the ventricle, a portion of the septum facing theventricle, a portion of tissue at a base of the papillary muscle, or aportion of the wall at the apex of the ventricle.)

Following the implantation of assembly 150 at site 5, tool 30 isdisengaged from assembly 150 when the physician pulls on tool 30. Thispulling pulls on manipulator 32 such that coupler 34 is actively movedradially outward against the ribs of docking station 56, and is therebydecoupled from station 56. At the time of pulling, tissue atimplantation site 5 pulls on assembly 150 (in the direction opposite thedirection of pulling by the physician) so as to help disengage tool 30from assembly 150.

As shown in FIG. 2, following the decoupling of tool 30 from assembly150, tool 30 is pulled proximally along guidewire 40 and is extractedfrom the body of the patient together with advancement sheath 22,leaving behind assembly 150 and guidewire 40.

FIG. 3 shows advancement of an implant (e.g., a spool assembly 36comprising an adjustment mechanism 43) along guidewire 40 by anadjustment-mechanism delivery tool 64, in accordance with someapplications of the present invention. Tool 64 is surrounded by andslidable within an advancement sheath 60 having a distal end 62.

Spool assembly 36 is surrounded by a braided fabric mesh, e.g., apolyester mesh, which promotes fibrosis around assembly 36 andfacilitates coupling of assembly 36 to tissue of heart 2. Assembly 36houses a rotatable structure (e.g., a spool as shown hereinbelow) thatis surrounded by a housing 49. Housing 49 is coupled to a distal cap 44which facilitates coupling of assembly 36 to docking station 56 ofdocking assembly 150. As shown, cap 44 is shaped so as to define aplurality of baffles 47 that are disposed angularly with respect to adistal end of cap 44. Baffles 47 are coupled to the distal end of cap 44along respective coupling joints which facilitate movement of eachbaffle 47. During the coupling of spool assembly 36 to docking station56, the ribbed portion of docking station 56 pushes inwardly baffles 47of cap 44, as is described hereinbelow. Baffles 47 then expand andengage an area of docking station 56 between the ribs of the ribbedportion so as to dock and lock assembly 36 to docking station 56.

Additionally, cap 44 is shaped so as to define a central openingtherethrough which facilitates passage therethrough of guidewire 40.Additionally, spool assembly 36 and the components thereof are shaped soas to define a central opening (i.e., an opening having the same axis asguidewire 40). That is, spool 46 has a central opening, and housing 49has a central opening which facilitates passage of spool 46 and housing49 along guidewire 40.

As shown, adjustment mechanism 43 is coupled to a distal portion of arepair chord 74 (e.g., repair chord 74 is looped through or otherwisecoupled to a portion of adjustment mechanism 43). Chord 74 comprises aflexible longitudinal member. For some applications, and as is describedhereinbelow, chord 74 functions as an artificial chordae tendineae. Aproximal portion of chord 74 is coupled to a leaflet-engaging element 72(e.g., a clip, as shown). Leaflet-engaging element 72 is disposed withina holder 70 that is coupled to delivery tool 64. Chord 74 asuperelastic, biocompatible material (e.g., nitinol, ePTFE, PTFE,polyester, stainless steel, or cobalt chrome). Typically, chord 74comprises an artificial chordae tendineae.

FIGS. 4-5 are schematic illustrations of the engaging ofleaflet-engaging element 72 to at least one leaflet 14 of a mitral valveof the patient, in accordance with some applications of the presentinvention. As shown in FIG. 4, the clip is opened from a remote locationoutside the body of the patient.

For some applications, the clip typically is shaped so as to define atleast one coupling protrusion 73. The clip has a tendency to close, andis initially held open by a cord (not shown) that is coupled to asurface of the clip, extends through delivery tool 64, and is heldtaught outside of the heart. Once the clip has been advanced to thedesired location on the leaflet, the cord is relaxed, allowing the clipto close. The cord is removed, typically by releasing one end thereofand pulling the other end. The positioning of holder 70 between theleaflets (FIG. 5) helps ensure that the clip engages exactly one of theleaflets. It is noted that in FIG. 5 the clip is shown engaging only asingle leaflet (leaflet 14). The clip typically engages the leaflet byclamping the leaflet such that the clip engages atrial and ventricularsurfaces of the leaflet. The clip may puncture the leaflet, or maymerely press firmly against the leaflet.

It is to be noted that the scope of the present invention include theclipping together of both leaflets 12 and 14. For applications in whichsystem 20 is used to repair a tricuspid valve of the patient, the clipmay clip any one, two, or all three leaflets together.

Holder 70 is shaped to define a groove which houses the clip during theadvancement of tool 64 toward the ventricle. The groove functions as atrack to facilitate slidable detachment of the clip from holder 70following the engaging of the clip to leaflet 14.

Alternatively, the clip has a tendency to open. In order to close theclip, a cord is provided. A distal-most portion of the cord is loopedaround the clip. Once the clip has been advanced to the desired locationon the leaflet, as shown in FIG. 5, the surgeon pulls on both ends ofthe cord, thereby causing the clip to become locked closed. The cord isremoved, typically by releasing one end thereof and pulling the otherend.

It is to be noted that the scope of the present invention includes anyleaflet-engaging element known in the art.

As shown in FIG. 5, portions 74 a and 74 b extend from leaflet-engagingelement 72 toward adjustment mechanism 43. Portions 74 a and 74 b defineportions of a single chord 74 that is looped through a portion ofmechanism 43. Alternatively, portions 74 a and 74 b represent twodistinct chords which are coupled at their distal ends to adjustmentmechanism 43 and at their proximal ends to leaflet-engaging element 72.

As shown, leaflet-engaging element 72 engages leaflet 14 prior tocoupling spool assembly 36 to docking station 56.

FIG. 6 shows spool assembly 36 being coupled to docking station 56, inaccordance with some applications of the present invention. Followingthe coupling of leaflet-engaging element 72 to leaflet 14, spoolassembly 36 is pushed distally toward docking station 56. Spool assembly36 is coupled to an advancement shaft 80 which pushes assembly 36. Shaft80 slides within a lumen of delivery tool 64 and within a lumen ofholder 70 so as to advance spool assembly 36, while leaflet-engagingelement 72 remains engaged with leaflet 14. Advancement shaft 80functions to advance distally spool assembly 36 and functions tofacilitate engagement between spool assembly 36 and docking station 56.

As described hereinabove, docking station 56 has one or more lockingmechanisms (e.g., one or more ribs 57, shown in the enlargedcross-sectional image of FIG. 6) which project laterally such that rib57 defines a shelf and an depressed area underneath the shelf (i.e., thecross-sectional diameter at rib 57 is larger than the cross-sectionaldiameter at the area underneath the shelf). As described hereinabove,cap 44 of assembly 36 is shaped so as to define a plurality of baffles47. As cap 44 engages docking station 56, baffles 47 are pushed inwardand upward angularly as each baffle slides against rib 57. After eachbaffle 47 passes the shelf of rib 57, the baffle engages the depressedarea underneath the shelf of rib 57, as shown in the enlargedcross-sectional image of FIG. 6. The shelf of rib 57 prevents upwardmovement of baffles 47 and thereby locks in place baffles 47 and cap 44with respect to docking station 56. Rib 57, therefore, comprises alocking mechanism so as to lock implant 42 (e.g., adjustment mechanism43) to tissue anchor 50.

Following the coupling of assembly 36 to docking station 56, spool 46 isrotated in a first rotational direction in order to advance with respectto spool 46 and contact with spool 46 successive portions of chord 74.For example, when the successive portions of chord 74 are advanced withrespect to spool 46, the successive portions of chord 74 are loopedaround spool 46. The rotating of spool 46 in the first rotationaldirection pulls tight and adjusts a length of chord 74 between leaflet14 and spool 46, in order to adjust a distance between leaflet 14 andimplantation site 5 and to facilitate coaptation between leaflets 12 and14, as is described hereinbelow.

Housing 49 is shaped so as to provide openings 41 a and 41 b for passagetherethrough of portions 74 a and 74 b, respectively, of chord 74 intohousing 49. For some applications of the present invention, portions 74a and 74 b define portions of a single chord 74 that is looped throughspool 46. For other applications, portions 74 a and 74 b define discretechords which are each coupled at respective distal ends thereof to spool46.

The enlarged, cross-sectional image of FIG. 6 shows spool 46 withinhousing 49. Spool 46 defines an upper surface 150, a lower surface 152,and a cylindrical body portion disposed vertically between surfaces 150and 152. Spool 46 is shaped to provide a driving interface, e.g., achannel, which extends from an opening provided by upper surface 150 toan opening provided by lower surface 152. A proximal portion of thedriving interface is shaped to define a threaded portion 146 which mayor may not be tapered. Threaded portion 146 of spool 46 is engageable bya threaded portion of a screwdriver head 92 of a screwdriver 90.Screwdriver 90 is coupled to a distal end of shaft 80. For someapplications, shaft 80 rotates screwdriver 90. For other applications,shaft 80 is shaped so as to define a lumen for advancement therethroughof a screwdriver-rotation tool that facilitates rotation of screwdriver90. Rotation of screwdriver 90 and screwdriver head 92 rotates spool 46,as the respective threaded portions of spool 46 and screwdriver head 92engage. The cylindrical body portion of spool 46 is shaped to define oneor more holes which function as respective coupling sites for coupling(e.g., looping through the one or more holes, or welding to spool 46 inthe vicinity of the one or more holes) of any number of chords 74 tospool 46.

Lower surface 152 of spool 46 is shaped to define one or more (e.g., aplurality, as shown) recesses 154 which define structural barrierportions 155 of lower surface 152. It is to be noted that any suitablenumber of recesses 154 may be provided, e.g., between 1 and 10 recesses,circumferentially or otherwise, with respect to lower surface 152 ofspool 46.

As shown, a locking mechanism 45 is disposed in communication with lowersurface 152 of spool 46 and disposed in communication with at least inpart to a lower surface of housing 49. Typically, a cap 44 maintainslocking mechanism 45 in place with respect to lower surface 152 of spool46 and lower surface of housing 49. For some applications, lockingmechanism 45 is coupled, e.g., welded, to the lower surface of housing49. Typically, locking mechanism 45 defines a mechanical element havinga planar surface that defines slits. It is to be noted that the surfaceof locking mechanism 45 may also be curved, and not planar. Lockingmechanism 45 is shaped to provide a protrusion 156 which projects out ofa plane defined by the planar surface of the mechanical element. Theslits of mechanism 45 define a depressible portion 128 that is disposedin communication with and extends toward protrusion 156. Depressibleportion 128 is moveable in response to a force applied thereto typicallyby an elongate locking mechanism release rod 94 which slides through alumen of screwdriver 90 and a torque-delivering tool that is coupledthereto.

It is to be noted that the planar, mechanical element of lockingmechanism 45 is shown by way of illustration and not limitation and thatany suitable mechanical element having or lacking a planar surface butshaped to define at least one protrusion may be used together withlocking mechanism 45.

Cap 44 is provided that is shaped to define a planar surface and anannular wall having an upper surface thereof. The upper surface of theannular wall is coupled to, e.g., welded to, a lower surface provided byhousing 49. The annular wall of cap 44 is shaped to define a recessedportion 144 of cap 44 that is in alignment with a recessed portion 142of spool housing 49.

As shown, a distal end 96 of locking mechanism release rod 94 pushesdistally on depressible portion 128 in order to unlock locking mechanism45 from spool 46. Pushing depressible portion 128 by locking mechanismrelease rod 94 pushes distally protrusion 156 within recessed portion142 of housing 49 and within recessed portion 144 of cap 44, which freesprotrusion 156 from recesses 154 of spool 46. Once protrusion 156 isreleased from recesses 154 of spool 46, the physician is able to rotatespool 46 bidirectionally in order to adjust a tension of chord 74.

When the physician rotates spool 46 in the first rotational direction,chord 74 is pulled tight, and leaflet 14 is drawn toward adjustmentmechanism 43 and toward anterior leaflet 12 of mitral valve 8.

In the resting state (i.e., prior to the rotation of spool 46 in orderto adjust chord 74, following coupling of leaflet-engaging element 72 toleaflet 14) chord 74 is wrapped around spool 46 a few times (e.g., threetimes, by way of illustration and not limitation). This winding providesexcess slack to chord 74 (in case portions 74 a and 74 b are coupled tootightly to leaflet 14). If the physician wishes to provide slack tochord 74 or to any one of portion 74 a or 74 b, the physician unwinds abit of the wrapped portion of chord 74 from around spool 46 (e.g., byunwinding chord 74 a few times from around spool 46, or by unwindingchord 74 entirely from around spool 46 so that chord 74 slides freelythrough spool 46 within a channel provided therein). In order toaccomplish such unwinding, the physician rotates spool 46 in arotational direction in which it unwinds the wrapped portion of chord74. Since chord 74 is looped through spool 46 in the channel providedtherein, when chord 74 is unwound from spool 46, the physician can pullon one or both portions 74 a and 74 b so as to adjust, make even, orfurther slacken any one of or both portions 74 a and 74 b that extendfrom spool 46.

When the physician desires to pull tight chord 74, he or she effectsrotation of spool 46 in a first rotational direction, i.e., thedirection opposite the second rotational direction in which spool 46 isrotated during the unwinding of chord 74 from spool 46. Rotation ofspool 46 in the first rotational direction winds chord 74 around spool46, while rotation of spool 46 in a second rotational direction that isopposite the first rotational direction, unwinds the portion oflongitudinal chord 74 from around spool 46.

FIG. 7 shows spool assembly 36 following the adjustment of chord 74 byrotating screwdriver 90 in the direction as indicated by the arrow, andthe partial removal of screwdriver 90, in accordance with someapplications of the present invention. As shown in the enlargedcross-sectional image of FIG. 7, successive portions of chord 74 arewrapped around spool 46. That is, chord 74 is wrapped more times aroundspool 46 following adjustment (e.g., an additional 4 times, as shown inFIG. 7), than prior to adjustment (FIG. 6). This pulls chord 74 from aslackened state (FIG. 6) to a taut state (FIG. 7) in order to adjust alength of chord 74 between adjustment mechanism 43 and the proximal endof chord 74 that is coupled to leaflet-engaging element 72.Additionally, this applying of tension to chord 74 adjusts a lengthbetween first and second implantation sites 5 and 7. Typically, chord 74is adjusted while heart 2 is beating.

As shown, rod 94 is shaped so as to define a central lumen and a distalopening for passage therethrough of guidewire 40. Additionally,depressible portion 128 is shaped so as to provide an opening forpassage of guidewire 40 therethrough. Guidewire 40 is looped around adistal looping element 55 of docking platform 54 of docking assembly150. Following the adjusting of the tension and length of chord 74,screwdriver 90 is decoupled from spool 46 (e.g., by being unscrewed fromthreaded portion 146 of spool 46) and is advanced proximally togetherwith rod 94 away from spool assembly 36, as shown in the enlarged,cross-sectional image of FIG. 7.

Following the decoupling of screwdriver 90 from spool 46 and the removalof screwdriver 90, guidewire 40 remains coupled to docking platform 54and docking assembly 150. Guidewire 40 then facilitates subsequentadvancement of screwdriver 90 or any other tool to access spool assembly36 and/or to facilitate further adjustment of chord 74 beyond theinitial adjustment. Guidewire 40 may remain chronically coupled todocking assembly 150 and may be accessible at a subcutaneous location ofthe patient, e.g., a port. For other applications, guidewire 40 isremoved from docking assembly 150 when the physician determines thatfurther adjustment of chord 74 is not needed. The physician removesguidewire 40 by pulling, from outside the body of the patient, one endof guidewire 40 so that guidewire 40 slides around element 55 and isunlooped therefrom. The physician continues to pull on the end ofguidewire 40 until the second end of wire 40 is exposed and removed fromthe patient.

Following the removal of locking-mechanism release rod 94, depressibleportion 128 is no longer depressed by distal end 96 of rod 94, andprotrusion 156 returns within a recess 154 of spool 46 so as to lockspool 46 in place and restriction rotation thereof in either direction(FIG. 7).

Reference is now made to FIGS. 3-7. It is to be noted that spoolassembly 36 is only coupled to docking assembly 150 following thecoupling of leaflet-engaging element 72 to leaflet 14. This is done inorder to reduce the strain on implantation site 5. Should spool assembly36 be implanted at implantation site 5 prior to engaging leaflet 14 withleaflet-engaging element 72, more strain would be applied toimplantation site 5 than if spool assembly 36 had been implantedfollowing the coupling of leaflet-engaging element 72 to leaflet 14, asdescribed herein. That is, the pulling force is applied in a downwarddirection from leaflet 14 toward implantation site 5 instead of fromimplantation site 5 upward toward leaflet 14.

FIG. 8 shows system 20 following the removal of the tool used to rotatespool 46 of spool assembly 36, in accordance with some applications ofthe present invention. As shown, chord 74 is pulled tight such that itslength and tension are adjusted, and leaflet 14 is pulled and adjustedcommensurate with the adjustment of chord 74. Guidewire 40 remainscoupled to spool assembly 36 and to docking assembly 150, as shown, suchthat portions 40 a and 40 a′ extend from spool assembly 36. Guidewire 40facilitates the reintroduction of the tool used to rotate spool 46, orof any other tool.

FIG. 9 shows system 20 following the removal of guidewire 40 from heart2, in accordance with some applications of the present invention. Asshown, the adjustment of chord 74 draws leaflets 12 and 14 together. Itis to be noted that although leaflet-engaging element 72 is shown asengaging only leaflet 14, the scope of the present invention includesthe engaging of both leaflets 12 and 14 by leaflet-engaging element 72.

FIG. 10 shows a system 220, as described hereinabove with reference tosystem 20, with the exception that implantation site 5 includes tissueof the wall of the ventricle at the base of papillary muscle 4 in avicinity of the apex of the heart, in accordance with some applicationsof the present invention. Implantation site 5 is shown by way ofillustration and not limitation, and as described hereinabove, site 5may include any portion of tissue of heart 2. It is to be noted thatalthough leaflet-engaging element 72 is shown as engaging only leaflet14, the scope of the present invention includes the engaging of bothleaflets 12 and 14 by leaflet-engaging element 72.

Reference is now made to FIGS. 11A-F, which are schematic illustrationsof a system 240 and techniques for use thereof, for delivering a tissueanchor 280 to a papillary muscle of a subject, in accordance with someapplications of the invention. For some applications of the invention,tissue anchor 280 comprises tissue anchor 50 of docking assembly 150,described hereinabove. Alternatively, tissue anchor 280 may comprise adifferent tissue anchor. Similarly, tissue anchor 280 may comprise ahelical tissue anchor, as shown in FIGS. 11A-F by way of illustrationand not limitation, or may comprise a different tissue anchor.

As described hereinabove (e.g., with reference to FIGS. 1-2),transcatheter access to heart 2 typically begins with the advancing of asemi-rigid guidewire into the left atrium of the patient, and sheath 28is subsequently advanced along (e.g., over) the guidewire, to the leftatrium. Typically, but not necessarily, this is performed using astandard transseptal puncture procedure, and further typically, theguidewire is advanced to the heart transfemorally, as shown.Alternatively, the guidewire may be advanced using a retrogradeapproach, via the aorta of the subject. Similarly, any suitable approachmay be used such as, but not limited to, those described with referenceto FIGS. 1-2. For some applications, such that those described withreference to FIGS. 11A-F, the guidewire is not immediately retractedfrom the body of the patient. The guidewire is shown in FIGS. 11A-F as aguidewire 242. Typically, guidewire 242 is advanced such that it passesleaflets 12 and 14, and reaches and/or passes one or more chordaetendineae 244 (FIG. 11A). For some applications, guidewire 242 passesbetween two or more chordae tendineae 244. For some applicationsguidewire 242 is configured (e.g., shape-set) to facilitate suchpositioning. FIG. 11A also shows a chord-engaging tool 246 beingsubsequently advanced distally along guidewire 242, toward chordaetendineae 244.

A distal portion of chord-engaging tool 246 comprises or defines ahousing 248, and the chord-engaging tool is advanced such that housing248 is disposed in a vicinity of (e.g., close to and/or touching) one ormore of the chordae tendineae (FIG. 11B). Typically, tool 246 (e.g.,housing 248 thereof) is shaped to define a channel 247 therethrough,through which guidewire 242 is slidable. Disposed within housing 248 isat least part of a guide member 250, which has a distal portion and aproximal portion. The distal portion of guide member 250 comprises achord-engaging element, such as, but not limited to, a helicalchord-engaging element 252, which is configured to be slidably coupledto at least one of the chordae tendineae.

FIG. 11B shows element 252 having been advanced out of an opening 249defined by housing 248, and forming a helix outside of the housing. Forsome applications, when disposed within housing 248, element 252 isgenerally straight (e.g., is held generally straight within a lumen ofthe housing), and curls into the helix as it emerges from the housing.Alternatively, element 252 is also helical when disposed within housing248. Element 252 wraps around one or more of the chordae tendineae asthe element forms the helix outside of the housing. For someapplications, element 252 is rotated to facilitate this wrapping.Similarly, housing 248, element 252, and guidewire 242 may bemanipulated (e.g., moved back and forth) to facilitate engagement of thechordae tendineae by element 252.

FIG. 11C shows chord-engaging tool 246 (including housing 248) beingsubsequently moved distally such that chord-engaging element 252 slidesdistally along the one or more chordae tendineae that have been engaged,such that element 252 reaches (e.g., touches) a papillary muscle 254(e.g., the papillary muscle to which the chordae tendineae engaged byelement 252 is coupled).

Subsequently, tool 246 (including housing 248) is withdrawn proximally,while guide member 250 is held in place (e.g., by a counter force), suchthat tissue-engaging element 252 remains coupled to the chordaetendineae in close proximity to (e.g., in contact with) papillary muscle254, and exposing the proximal portion of guide member 250, comprising alongitudinal element 251. Typically, tool 246 (including housing 248) issubsequently withdrawn into sheath 28, and further typically, isdecoupled from the guide member and/or removed from the body of thepatient.

FIG. 11E shows a deployment tool 260 being transcatheterally advancedinto heart 2 of the subject, and being slid along guide member 250(e.g., along longitudinal element 251 thereof). For some applications,tool 260 comprises one or more eyelets 262, slidable over longitudinalelement 251. For some applications, tool 260 is advanced via an overtube258, which may itself be advanced through sheath 28. For someapplications, tool 260 is advanced via tool 246 (e.g., via a lumentherethrough), and overtube 258 in FIGS. 11E-F represents tool 246functioning as an overtube.

Guide member 250 (e.g., longitudinal element 251 thereof) guidesdeployment tool 260 toward papillary muscle 254. For some applications,deployment tool 260 comprises a distal lance 264, configured topenetrate tissue of papillary muscle 254, and to stabilize tool 260 atthe papillary muscle. For some such applications, lance 264 isretractable into the body of tool 260. For applications in whichdeployment tool comprises lance 264, the lance is typically slidablethrough a hole in anchor 280. Alternatively, anchor 280 may compriselance 264, and the lance is configured to stabilize the anchor at thepapillary muscle during anchoring, e.g., during rotation of the anchor.

Deployment tool 260 is configured to anchor tissue anchor 280 topapillary muscle 254. For some applications, and as shown in FIG. 11E,tissue anchor 280 is reversibly coupled to the distal end of tool 260.For some applications, the tissue anchor is housed within tool 260 andis advanced out of the tool prior to or during anchoring. Forapplications in which anchor 280 comprises a helical anchor, the anchoris typically anchored to the papillary muscle by being rotated by tool260, or by a component thereof.

For some applications, system 240 is configured to facilitate anchoringof tissue anchor 280 to other ventricular muscle tissue in the vicinityof papillary muscle 254 (e.g., within 1 cm of the papillary muscle). Forexample, a sufficient distance between (1) a distal-most part of tool260 at which the tool is slidably coupled to longitudinal element 251(e.g., the distal-most eyelet 262), and (2) a distal end of anchor 280may be provided to allow the tissue anchor to be anchored slightly awayfrom chord-engaging element 252 (e.g., within 1 cm of the papillarymuscle). Flexibility of longitudinal element 251 may alternatively oradditionally facilitate such anchoring of anchor 280. Alternatively oradditionally, the operating physician may stop advancing tool 260 suchthat a length of guide member 250 (e.g., of longitudinal element 251thereof) between the distal-most eyelet 262 and chord-engaging element252 is sufficient to facilitate such anchoring of anchor 280.

FIG. 11F shows guide member 250 and deployment tool 260 having beenretracted proximally (e.g., into overtube 258 and/or out of the body ofthe patient), exposing a guidewire 282, reversibly coupled to anchor280, and extending proximally (e.g., into overtube 258 and/or out of thebody of the subject).

Chord-engaging element 252 is typically decoupled from chordae tendineae244 by withdrawing guide member 250 slightly proximally with respect totool 260, thereby straightening out the helix formed by element 252. Forexample, the helix may be progressively drawn into tool 260, or past aneyelet 262 thereof, and responsively straighten. Alternatively,chord-engaging element 252 may be decoupled from the chordae tendineaeusing tool 246 (e.g., housing 248 thereof), such as by re-advancing thetool distally, and withdrawing member 250, including element 252thereof, into the tool.

For some applications, chord-engaging element 252 is decoupled fromchordae tendineae 244 after anchoring of tissue anchor 280 (e.g., aftertissue anchor 280 has been partially or fully advanced into papillarymuscle 254). For some such applications, this is facilitated byflexibility of element 252 (e.g., that which facilitates curling andstraightening thereof), e.g., by facilitating movement of element 252through and/or around portions of anchor 280.

For some applications, chord-engaging element 252 is decoupled fromchordae tendineae 244 prior to anchoring of tissue anchor 280. Forexample, chord-engaging element 252 may be decoupled from the chordaetendineae subsequently to lance 264 penetrating tissue and therebystabilizing tool 260 and anchor 280 with respect to the tissue.

It is to be noted that guidewire 282 is a different guidewire toguidewire 242, described with reference to FIGS. 11A-B. As describedhereinabove, for some applications, tissue anchor 280 comprises tissueanchor 50 of docking assembly 150. Similarly, guidewire 282 may compriseguidewire 40, described hereinabove, and may be reversibly coupled toanchor 280 via a docking station 56 of the docking assembly.

It is to be noted that, although guidewire 242 is shown in FIGS. 11A-Eas being present in heart 2, and is shown in FIG. 11F as having beenwithdrawn from the heart, guidewire 242 may be withdrawn at any point inthe procedure following the coupling of chord-engaging element 252 tochordae tendineae 244 (FIG. 11B).

For some applications, the step shown in FIG. 11F is generally similarto the step shown in FIG. 2. The apparatus and techniques described withreference to FIGS. 11A-F may be used in combination with the apparatusand techniques described with reference to FIGS. 1-10, e.g., tofacilitate anchoring of docking assembly 150 to a papillary muscle. Forsome such applications, the step described with reference to FIG. 11Fmay precede the step shown in FIG. 3, mutatis mutandis.

For some applications of the present invention, systems 20, 220, and 240are used to treat an atrioventricular valve other than the mitral valve,i.e., the tricuspid valve. For these applications, systems 20, 220, and240 placed in the right ventricle instead of the left ventricle.

It is to be noted that the scope of the present invention includes theuse of systems 20, 220, and 240 on other cardiac valves, such as thepulmonary valve or the aortic valve.

It is to be further noted that the scope of the present inventionincludes the use of systems 20, 220, and 240 on other tissue other thancardiac tissue, e.g., gastric tissue or any other suitable tissue ororgan.

For some applications, system 240 and/or the techniques described withreference to FIGS. 11A-F may be used to deliver a plurality of tissueanchors 280 to the papillary muscle, and/or to deliver a plurality oftissue anchors to a plurality of papillary muscles.

Additionally, the scope of the present invention includes applicationsdescribed in the following applications, which are incorporated hereinby reference. In an application, techniques and apparatus described inone or more of the following applications are combined with techniquesand apparatus described herein:

-   -   PCT Publication WO 06/097931 to Gross et al., entitled, “Mitral        Valve treatment techniques,” filed Mar. 15, 2006;    -   U.S. Provisional Patent Application 60/873,075 to Gross et al.,        entitled, “Mitral valve closure techniques,” filed Dec. 5, 2006;    -   U.S. Provisional Patent Application 60/902,146 to Gross et al.,        entitled, “Mitral valve closure techniques,” filed on Feb. 16,        2007;    -   U.S. Provisional Patent Application 61/001,013 to Gross et al.,        entitled, “Segmented ring placement,” filed Oct. 29, 2007;    -   PCT Patent Application PCT/IL07/001503 to Gross et al.,        entitled, “Segmented ring placement,” filed on Dec. 5, 2007        (which published as WO 2008/068756);    -   U.S. patent application Ser. No. 11/950,930 to Gross et al.,        entitled, “Segmented ring placement,” filed on Dec. 5, 2007,        which published as US Patent Application Publication        2008/0262609 (now U.S. Pat. No. 8,926,695);    -   U.S. Provisional Patent Application 61/132,295 to Gross et al.,        entitled, “Annuloplasty devices and methods of delivery        therefor,” filed on Jun. 16, 2008;    -   U.S. patent application Ser. No. 12/341,960 to Cabiri, entitled,        “Adjustable partial annuloplasty ring and mechanism therefor,”        filed on Dec. 22, 2008, which published as 2010/0161047 (now        U.S. Pat. No. 8,241,351);    -   U.S. Provisional Patent Application 61/207,908 to Miller et al.,        entitled, “Actively-engageable movement-restriction mechanism        for use with an annuloplasty structure,” filed on Feb. 17, 2009;    -   U.S. patent application Ser. No. 12/435,291 to Maisano et al.,        entitled, “Adjustable repair chords and spool mechanism        therefor,” filed on May 4, 2009, which published as 2010/0161041        (now U.S. Pat. No. 8,147,542);    -   U.S. patent application Ser. No. 12/437,103 to Zipory et al.,        entitled, “Annuloplasty ring with intra-ring anchoring,” filed        on May 7, 2009, which published as 2010/0286767 (now U.S. Pat.        No. 8,715,342);    -   PCT Patent Application PCT/IL2009/000593 to Gross et al.,        entitled, “Annuloplasty devices and methods of delivery        therefor,” filed on Jun. 15, 2009, which published as WO        10/004546;    -   U.S. patent application Ser. No. 12/548,991 to Maisano et al.,        entitled, “Implantation of repair chords in the heart,” filed on        Aug. 27, 2009, which published as 2010/0161042 (now U.S. Pat.        No. 8,808,368);    -   U.S. patent application Ser. No. 12/608,316 to Miller et al.,        entitled, “Tissue anchor for annuloplasty ring,” filed on Oct.        29, 2009, which published as 2011/0106247 (now U.S. Pat. No.        8,277,502);    -   PCT Patent Application PCT/IL2009/001209 to Cabiri et al.,        entitled, “Adjustable annuloplasty devices and mechanisms        therefor,” filed on Dec. 22, 2009, which published as WO        10/073246;    -   U.S. patent application Ser. No. 12/689,635 to Zipory et al.,        entitled, “Over-wire rotation tool,” filed on Jan. 19, 2010,        which published as 2010/0280604 (now U.S. Pat. No. 8,545,553);    -   U.S. patent application Ser. No. 12/689,693 to Hammer et al.,        entitled, “Application Deployment techniques for annuloplasty        ring,” filed on Jan. 19, 2010, which published as 2010/0280605        (now U.S. Pat. No. 8,911,494);    -   U.S. patent application Ser. No. 12/706,868 to Miller et al.,        entitled, “Actively-engageable movement-restriction mechanism        for use with an annuloplasty structure,” filed on Feb. 17, 2010,        which published as 2010/0211166 (now U.S. Pat. No. 8,353,956);        and/or    -   U.S. patent application Ser. No. 12/795,026 to Miller et al.,        entitled, “Apparatus for guide-wire based advancement of a        rotation assembly,” filed on Jun. 7, 2010, which published as        2011/0106245 (now U.S. Pat. No. 8,940,042).

It will be appreciated by persons skilled in the art that the presentinvention is not limited to what has been particularly shown anddescribed hereinabove. Rather, the scope of the present inventionincludes both combinations and subcombinations of the various featuresdescribed hereinabove, as well as variations and modifications thereofthat are not in the prior art, which would occur to persons skilled inthe art upon reading the foregoing description.

1-13. (canceled)
 14. A method for use with a papillary muscle of a heartof a subject, the papillary muscle being coupled to a chorda tendinea ofthe heart of the subject, the method comprising: transluminallyintroducing a sheath into an atrium of the heart; advancing a guidemember out of the sheath and to the chorda tendinea, the guide memberhaving a proximal portion that includes a longitudinal element, and adistal portion that includes a helical chord-engaging element; wrappingthe chord-engaging element around chorda tendinea; and while thechord-engaging element remains wrapped around the chorda tendinea:sliding the chord-engaging element over the chorda tendinea toward thepapillary muscle; and subsequently, moving a tool out of the sheath andtoward the papillary muscle by sliding the tool along the longitudinalelement.
 15. (canceled)
 16. The method according to claim 14, furthercomprising, following the step of advancing, anchoring a tissue anchorto ventricular muscle tissue using the tool.
 17. The method according toclaim 16, wherein anchoring the tissue anchor comprises anchoring thetissue anchor to ventricular muscle tissue in a vicinity of thepapillary muscle.
 18. The method according to claim 17, whereinanchoring the tissue anchor comprises anchoring the tissue anchor toventricular muscle tissue within 1 cm of the papillary muscle.
 19. Themethod according to claim 17, wherein anchoring the tissue anchorcomprises anchoring the tissue anchor to the papillary muscle.
 20. Themethod according to claim 16, wherein anchoring the tissue anchorcomprises anchoring a tissue anchor that is reversibly coupled to aguidewire.
 21. The method according to claim 16, wherein the toolincludes a lance, and the method further comprises, prior to anchoringthe tissue anchor, stabilizing the tool with respect to the ventricularmuscle tissue by penetrating the ventricular muscle tissue with thelance.
 22. The method according to claim 21, further comprisingretracting the lance into the tool.
 23. The method according to claim14, wherein the step of advancing further comprises advancing, to theheart of the subject, a housing that is slidable along the guide member.24. The method according to claim 23, further comprising, prior to thestep of advancing, advancing a guidewire to a ventricle of the heart,wherein advancing the housing comprises sliding the housing over theguidewire.
 25. The method according to claim 24, wherein advancing theguidewire comprises advancing a distal portion of the guidewire betweenat least two chordae tendineae of the subject.
 26. The method accordingto claim 23, further comprising, subsequent to the step of advancing,sliding the chord-engaging element distally out of the housing.
 27. Themethod according to claim 26, further comprising, subsequent to the stepof wrapping and prior to the step of moving, proximally withdrawing thehousing and decoupling the housing from the guide member whilemaintaining the chord-engaging element wrapped around the chordatendinea.
 28. The method according to claim 26, wherein sliding thechord-engaging element distally out of the housing comprisestransitioning the chord-engaging element from a generally straight stateinto a helical state. 29-40. (canceled)